Virtual workstations for 3D CAD and BIM applications: the 6 different flavors (and their costs)

Choices, choices, choices

3D CAD and BIM software have always demanded a lot of raw power. And this is why, until recently, it was only really possible to run them on local machines - on your desktop in the office. 

But advances in cloud computing have been a real game changer. It is now possible to run CAD and BIM applications using remote desktop virtualization. You can either outsource the computing (using a software-as-a-service model) or build your own virtual desktop in a private cloud. 

In this guide, we’ll explore the different options available if you wish to use a virtual workstation for your 3D CAD and BIM tools. We then summarize the costs of each option. 

Why use virtual workstations for 3D CAD and BIM?

There are multiple reasons to use virtual workstations for 3D CAD and BIM software. These include:

• Supports remote working (especially during lockdowns)
• Lets you hire CAD and BIM talent from anywhere in the world
• Potentially more secure than using on-premises machines
• Lets you treat computing power as OpEx rather than CapEx
• Allows you to be more flexible

Summary of CAD/BIM virtual workstation costs

There are two broad options for using CAD and BIM software on a virtual workstation. Here’s a summary of what each will cost you:

Option one (in 2 flavors): Desktop-as-a-Service. 

• A flat-fee plan costs $70 on average, per user, per month. 
• For a usage-based plan, it will come to $128 on average, per user, per month. 

Option two (in 4 flavors): Managed VDI:

• Virtual Desktop Infrastructure on Cloud Infrastructure, which costs $88 on average, per user, per month.
• Frame-managed cloud-based GPU Instances, which costs $129 on average, per user, per month
• Windows Virtual Desktop on Microsoft Azure, which costs $44 on average, per user, per month
• Virtual Desktop Infrastructure on Bare-Metal Machines With Grid Cards, which costs $131 on average, per user, per month

Comparing apples with apples

For the purpose of comparing the different options, we will use the following reference specifications for our virtual workstations:  

• 16GB of RAM
• Multiple Cores
• 2 GB of Video RAM
• 100 GB of SSD Disk
• Windows Operating System

We also assume the following user numbers: 

• 5 casual users of CAD or BIM software: e.g. Project Managers who need access to a CAD or BIM system one day per week

• 10 part-time users: e.g. architects, design engineers or part-time draftsmen, who need a virtual machine for half of their working time

• 10 full time users: staff that work with CAD or BIM most of the time

Don’t worry if you have a different setup. We’ll explain all the calculations, so you can adjust the numbers for your particular scenario. 

Option 1: Desktop-as-a-Service  

In the Desktop-as-a-Service (DaaS) model, the DaaS provider will host and maintain the hardware itself. They also handle storage and infrastructure. You pay them a fixed monthly fee and install your software licenses on the machine.

The following graphic demonstrates how this option works. You can use any internet connected laptop or PC to then connect remotely to the virtual desktop. 

So, what does it cost? There are a couple of options when it comes to payment.  

A: Bundles

First up are bundles of desktop access. You pay a flat rate for a specific number of hours of computing power. For example, with our reference workstation, 50 hours per month would cost $30, 100 hours costs $60, 200 hours costs $90. 

In addition to this, you will probably need a Microsoft Windows Client Access License (CAL) license. This license is necessary to legally access a server-based virtual workstation from a networked computer (It is very likely, that Desktop-as-a-Service providers will offer a server-based machine with Windows Server as the operating system). A CAL is not a software product; rather, it is a license that gives a user the right to access the services of the server. The cost for this CAL is $4 per user, per month. 

So how does that add up for our reference team for one month? The following table summarizes the costs: 

	Hours per month	Number of users	Monthly Bundle	CAL License	Monthly user cost	Monthly Cost (Total)
Light Users	40	5	$30.00	$4.00	$34.00	$170.00
Part-time Users	80	10	$60.00	$4.00	$64.00	$640.00
Fulltime Users	160	10	$90.00	$4.00	$94.00	$940.00
						$1,750.00

B: Usage-based

An alternative approach is usage-based DaaS. With a usage-based offering, our reference client would pay a flat fee ( $20) and then a $1 pay-per-hour charge for each user.  

The monthly costs for this option for the reference team are: 

	Hours per month	Number of users	Monthly Fee	Usage Cost per hour	CAL License	Monthly Cost (Total)
Light Users	40	5	$20.00	$1.00	$4.00	$320.00
Part-time Users	80	10	$20.00	$1.00	$4.00	$1,040.00
Fulltime Users	160	10	$20.00	$1.00	$4.00	$1,840.00
						$3,200.00

 

The monthly cost, based on the reference virtual workstation and team composition, ranges between $1,750 and $3,200 per month. With our 25 users this is between $70 (Flat Fee) and $128 (Usage based) per month. 

Option 2: Managed virtual desktop infrastructure 

In this set up, you (or an IT Provider) build up your own Virtual Desktop Infrastructure. The layout of each of the three “flavors” is depicted below, using virtual machines in the cloud. 

A: Virtual Desktop Infrastructure on cloud-based GPU Instances

In this flavor, the Virtual Desktop Infrastructure is built up using classic Virtual Desktop Software such as Citrix or VMware Horizon View. It would use special, “compute optimized” virtual cloud instances that also have GPU power (the graphics capabilities required for 3D applications) with Cloud Service Providers such as AWS or Microsoft Azure. 

The cost can be broken down into four components: 

1. Data Transfer (for the streaming)
2. Software
3. Cloud Based Instances
4. Management Cost 

1: Cost for Data Transfer

Cloud Service Providers charge for data traffic that leaves their cloud data centers (typically via the internet) to your “endpoints” - the actual end-user device from which your users are working with their CAD and BIM applications. 

The cost of this data transfer is $0.09 per Gigabyte. To estimate how much data is transferred per user, per hour, we have used the following assumption: 

• An average 90-minute, 1080 HD movie with 30 frames per second generates 3 GB in data traffic
• 60 minutes of this movie generates 2 GB in traffic
• A CAD or BIM session generates 60% of the traffic of an average HD movie 
• A CAD or BIM session generates 1.2 GB in traffic
• 1.2 GB costs $0,108 per hour. 

This is summarized in the table below: 

Cost of Network Traffic, per hour
Network traffic, per hour	1.2	GB
Traffic price	$0.09	Per GB
Traffic price, per user, per hour	$0.108

 

2: Cost of software

There are two major software cost components to consider. 

• Microsoft Windows Client Access License (CAL) license. As discussed , this license is necessary to legally access a server-based virtual workstation from a networked computer.The cost for this CAL is $4 per user, per month. 
• Virtual Desktop Infrastructure (VDI) software. This software lets you manage virtual desktops remotely, including control of things like backend components, operating systems, desktop image management, networking, layering and so on. The cost for this software is about $16 per user, per month. 

These costs are summarized in the following table

Software
Windows Client Access License	$4.00	Per User, per month
VDI Software	$15.00	Per User, per month
Total	$19.00	Per User, per month

3. Cost of running Cloud-Based compute instances

With the VDI running in a cloud environment, there’s no need to purchase any hardware in advance. As your users start working on CAD and BIM applications, you can spin up the virtual computers (and shut them back down). These virtual machines need to be specialized for compute operations and have a GPU attached to them. The hourly cost for a machine that can host up to four of our reference machines is $1.14 per hour. 

This cost is summarized below:

Costs for Compute with GPU
GPU-Based Compute Instance	$1.14	Per Hour
Users per Compute Instance	3
	$0.380	per user, per hour

Alongside the virtual instances, you’ll need virtual servers to run the VDI (management) software and (perhaps) a virtual machine for a so-called ‘netscaler’. We’ll assume that you’ll settle on one for each (this is acceptable for very small environments). These machines need to run 24x7. The netscaler needs a bigger machine than the VDI management software. The monthly cost is $100 for a VDI Management machine and $200 for the netscaler. 

The table below summarizes the monthly costs for the cloud-based compute instances. 

Virtual Servers for Management Software
Virtual Server for VDI Infrastructure	$100.00	Per month
Virtual Server for Netscaler	$200.00	Per month
Compute Cost, Total	$300.00	Per month
Number of users	25
Compute Cost, Per User	$12.00	Per month

4: Management Costs

Finally, this environment needs to be set up, managed and monitored. The cost for doing this is 10% of the cost for the cloud services (the network cost and the compute cost). 

In the table below, the costs are summarized for our reference team on a per-month basis. 

	Hours per month	Number of users	Traffic Costs	Software Cost	Monthly Compute Cost	Compute Overhead Cost	Management Cost	Total Cost
Light Users	40	5	$21.60	$95.00	$76.00	$60.00	$15.76	$268.36
Part-time Users	80	10	$86.40	$190.00	$304.00	$120.00	$51.04	$751.44
Full Time Users	160	10	$172.80	$190.00	$608.00	$120.00	$90.08	$1,180.88
								$2,200.68

With 25 users, this adds up to $88.03 per user, per month. 

B: Fra.me-managed cloud-based GPU Instances

The difference between this set-up and the previous option is that the VDI software is replaced with an alternative, cloud-based solution that has similar capabilities to the VDI software. Since it is a cloud-based service, setting up Fra.me is mostly a matter of configuring it to your requirements. With its built-in management capabilities and automation, it doesn’t require much effort to keep it running. The image below shows how this works. 

The major differences with this setup compared to VDI on Cloud are: 

• The subscription fee for Fra.me is $33. This replaces the cost for the VDI software ($16). 
• There’s no need for virtual servers for the VDI software and the Netscaler. 
• The instances for GPU + compute are different. Instead of having a big machine that is split in four by the VDI software, you will use instances that have the exact spec of the reference virtual workstation. This cost is $0.676 per hour plus $0.10 for the attached GPU.  
• This needs virtually no management, so the management cost is not applicable. 

Below are the costs for the different cost components

1: Data transfer cost

Cost of Network Traffic, per hour
Network traffic, per hour	1.2	GB
Traffic price	$0.09	Per GB
Traffic price, per user, per hour	$0.108

 

2: Software cost

Software costs
Frame software	$33.00	User/month
Microsoft Windows CAL	$4.00	User/month
Total	$37.00	User/month

3: Compute Cost

Compute Costs
Virtual Machine c5a.2xlarge w/100 GB	0.676	Machine/Hour
Elastic Graphics (eg1.large, 2 GiB)	0.1	Machine/Hour
Total	0.776	Machine/Hour

In the table below, the costs are summarized for our reference team on a per-month basis. 

Frame-managed Cloud Machines
	Hours per month	Number of users	Monthly Traffic Costs	Software Cost	Monthly Compute Cost	Total Cost
Light Users	40	5	$21.60	$185.00	$155.20	$361.80
Part-time Users	80	10	$86.40	$370.00	$620.80	$1,077.20
Full Time Users	160	10	$172.80	$370.00	$1,241.60	$1,784.40
						$3,223.40

With 25 users, this comes out as $128.94 per user, per month. 

C: Windows Virtual Desktops 

The setup is similar to the FRA-ME based architecture: as the picture below shows, the Windows Virtual Desktop-service on Azure replaces the FRA.ME software. The second difference is that it is much less likely that you will need a CAL license. 

You might be wondering why you probably don’t need a CAL. The reason is that the Virtual Instances come with the Windows 10 Operating System (OS). All the other options we have shown come with the Windows Server OS, for which this additional CAL is needed. Here’s a Microsoft article that can help you determine if you would need a CAL with the Windows Virtual Desktop. The assumption in our cost calculations is that you don’t need a CAL.  

As part of their service, Microsoft offers a cost estimator. A quirk of this tool is that the minimal amount of users is 100. To get around this limitation, the cost calculation is done in two steps. 

In the first step, the cost per 100 users is calculated. This total cost is then divided by 100. The result is then the monthly cost per user.  Below are the results: 

Windows Virtual Desktop - Results From Microsoft Cost Calculator (Monthly)
Users	Hours/Month	Compute	Storage	Traffic	Total, 100 users	Monthly Cost per user
100	50	$1,495.20	$115.20	$303.08	$1,913.48	$19.13
100	100	$2,875.20	$115.20	$540.58	$3,530.98	$35.31
100	200	$5,520.00	$115.20	$1,015.49	$6,650.69	$66.51

The second step is to calculate the monthly total cost, starting with the monthly cost per user. The results are shown in the table below. 

Monthly Cost per user	Nr. of Reference users	Total
$19.13	5	$95.67
$35.31	10	$353.10
$66.51	10	$665.07
		$1,113.84

The monthly total cost for the reference client and the reference team is $1,113.84. The average price per user (for 25 users) is $44.55

D: Virtual Desktop Infrastructure on Bare-Metal Machines With Grid Cards

In this option, the Virtual Desktop Infrastructure is built up with classic Virtual Desktop Software such as Citrix or VMware Horizon View, running on special “bare metal” machines with GPU Grid that provide the GPU power. This, together with the storage components and networking equipment runs in a datacenter. A part-time system administrator runs this rig. 

The cost can be broken down into four components: 

1. Software
2. Cost for hardware
3. Cost for the datacenter
4. Management Cost 

Note: there is no charge for the data traffic going out to the internet. 

1: Software costs

There are the two main software cost components to consider. 

• Microsoft Windows Client Access License (CAL) license. The cost for this license, in this case, is about $4 per user, per month. 
• Virtual Desktop Infrastructure (VDI) software. The cost for this software is about $16 per user, per month

2: Costs for hardware

The other major cost component is for the acquisition of CPU’s, Graphics Cards, Storage, Cables, and Software to manage the hardware. It’s useful to remember that the capacity of this hardware should be based on ~70% of total users, as they are not all full-time users (at least not in our reference team). To calculate the monthly cost of this equipment, we assume a life-time of three years, or 36 months:

Monthly cost of the Hardware
Racks, CPU, Graphic Cards, Storage, HW Management Software	$25,000.00
Amortization	36	Months
	$694.44	Per month

3: Datacenter hosting cost

The hardware needs to be hosted in a datacenter, which also provides security, power, cooling and connectivity. Four racks would be needed for this setup, the cost for each rack is $125 per month. 

The datacenter costs are summarized in the table below. 

Datacenter Hosting Cost
Cost per Rack	$125	per month
Racks	4
Monthly hosting costs	$500	Per month

4: Management costs

The hardware and software will need to be monitored, managed and updated by a system administrator. This will take a day per week on average. The fully loaded costs of a system administrator are $8000. 

The management cost are detailed in the table below:

Management cost
Effort to manage the environment	0.2	FTE/Month
Monthly Cost/FTE	$8,000.00	Per FTE/Month
Management cost	$1,600.00	Per month

The next table summarizes all these costs

	Nr. of users	Monthly cost
Software	25	$475.00
Monthly Hardware amortization		$694.44
Monthly Hosting cost		$500.00
Monthly Management Cost		$1,600.00
		$3,269.44

With a monthly cost of $3,269.44 for 25 users, the cost per user per month for this setup is $130.78. 

Know the costs of virtual workstations for 3D CAD and BIM

As we’ve seen, there are several different options for setting up and paying for virtual workstations for 3D CAD and BIM software. 

The table below summarizes the costs of each of the options we’ve described:

Monthly cost of running CAD and BIM applications in different virtual environments
	Monthly Cost	Monthly Cost per User
Windows Virtual Desktop	$1,113.84	$44.55
Desktop-as-a-Service: Flat Plan	$1,650.00	$70.00
VDI on Cloud Infrastructure	$2,200.68	$88.03
Desktop-as-a-Service: Usage Based	$3,100.00	$128.00
Fra.me on Cloud	$3,223.40	$128.94
VDI on Bare Metal	$3,269.44	$130.78

As the table shows,Windows Virtual Desktop  is the lowest-cost option for running 3D applications in a virtual environment. For many organizations, this will be the most attractive option if they have the adequate skills to run and manage this. 

However, costs should not be your only criteria when it comes to making a decision about a virtual environment. Even with higher costs, for example, running a VDI on “bare metal” in a datacentre may make sense if that's the only viable option to run your preferred BIM or CAD programs in a virtual environment. 

Besides pricing, you should also pay attention to how well your 3D application performs in the virtual environment. If your users perceive it as sluggish or slow, you won’t reap the benefits. The ‘big three’ factors that determine the performance of virtual environments are:

1. The specs (RAM, GPU, Disk, Cores) of the virtual machine, 
2. The bandwidth of the internet connection, and 
3. The latency between the client (the end user) and the host (the virtual machine) 

For a helpful guide on deciding which set up is right for you, read our comparison: CAD in the cloud - when is it right for you?